Written by Doug Crouch

Chapter 5 of the Designer’s Manual is still at the patterns level of the Permaculture adage “from patterns to details“.  The details emerge in the later chapters when the climate groups are broken down further in temperate, tropics, and drylands.

For now, we still need to have a closer look on why climate is something we examine in our everyday design work. Below is a great list that reflects Mollison’s checklist approach:

The first point refers to the fact that we simply need to know what plants we can grow in which climates.

Growing mangos is not possible in Ohio nor really in Portugal, even though we tried. Paw Paws –Asimina triloba- are definitely possible in Ohio. Its cousin though, the Cherimoya (Annona cherimola), thrives in Portugal.

This is also true of animals as we had sheep in the humid lowland tropics of Costa Rica but those will be a different breed than those raising sheep in Manitoba, Canada.

From a universal approach to localism

It is important to realize, that we cannot “rubber stamp” a universal model of development. Building materials that are brought in from outside might not be suitable for housing in a specific climatic zone. Agricultural methods for temperate climates do not have the same effects in the tropics or drylands. Techniques that are indicative of Permaculture –like swales and food forest– will be different depending on the climate.

We must always examine the context for design and not just rush and blindly develop for future, continued consumption. Thus our buildings must reflect this trend as well, carefully taking into account thermal mass and insulation properties of building materials and design. Climate and natural environment dictate the design. Far too often we brought our building materials and types of agriculture from the temperate world into the tropical zone with tremendous downfall. It is vital for our world to progress or re-gress in a fashion that brings the idea of local to all.

In Malaysia, 2009, I lived in a concrete house, which is a British construct, and it was a disastrously moldy house. Vernacular dwellings were built with wood, used very light materials, and designed for high shade and airflow. This was the opposite of how the British development imposition unfolded.

Design Considerations

The below slide shows more factors pertinent to design and climate and a broader understanding of how climates are shaped. Extremes in temperature and rainfall are important to plan for these days because of the way that global climate shift is happening.

Extremes. I am not a climatologist, a scientist of no sorts, but have been observing weather closely my whole life because of my father and then my own interest as it pertains to agriculture and the environment in general. What I have noticed over my life is that the things, that were once consistent, are no longer so and the extremes have set in.

For example in the Cincinnati, Ohio, USA, region where I hail from, it typically has 40 inches (101 cm) of rainfall per year fairly evenly distributed throughout the year. However, the last few years have shown the extremes.

The extreme trend has shown that 2010 was a drought year, 2011 was a rainfall total of 70 inches (178 cm, nearly double our average), and then 2012 was a drought year once more. So we must plan and design for these extremes. I am glad I put my swale in both of those contexts.

Precipitation. Rainfall totals should be examined both in total but also in distribution. Both Berlin, Germany and Sintra, Portugal (where our project Terra Alta is) receive nearly identical amounts of yearly rainfall yet have two totally different climates. Berlin receives a fairly equally distribution, whereas Sintra shows the classic wet season of a Mediterranean climate for five to seven months while the rest of the year is bone dry.

This ties into what the Holistic Management movement refers to as the “Brittleness Scale”. Those climates that receive a more equal distribution are less “brittle” than those that have sporadic or extended dry periods. Our management strategies must be altered when switching these contexts.

Fog. In some coastal areas, Mollison notes, that it is important to recognize the heavy influence of fog as it can inhibit flowering. This is stimulated by light and I know from years in Portugal where we had unuasually heavy summer fogs similar to those in San Francisco, we had lower tomato yields.

Continental effects. When looking at your climate, do note that when you are in the interior of the continent, you will be experiencing more temperature extremes. Cincinnati in Ohio, Sintra in Portugal, and Nelson in New Zealand all have similar latitude but the later two are classified as sub-tropical because of the maritime effect. The ocean creates a tempered effect because of its large thermal mass. This is why England and Kodiak Island, Alaska, have such a mild climate despite its latitude as the warm ocean current delivers milder temperature regimes.

Altitude. Also altitude has a large degree of influence on the climate of a region. It’s why Kilimanjaro used to have snow on its peak even though it sits at the equator.  It’s why my work in Jarabacoa, Dominican Republic, was much more sub-tropical in its feel despite heading south from the North Coast. By going up 3,000 feet, it was like I was going back to the States in a way. As it states above, for every 100 meters of altitude you rise it’s like moving away from the equator by 1 degree.  Amazing, but a good friend of mine called me once from Guatemala and said, “Hey what do y’all grow in Portugal because I am basically in a Mediterranean climate because of the altitude?”  So I rattled off a list of plants and he went on to track many of them down.

Wind. Finally there are a few things you can do on-site to understand some climate patterns. The first one is instantaneous. You can look at the trees on site and notice a phenomenon called “tree flagging”. This is when damaging winds create a tree with an unbalanced spherical look with the windward side showing less foliage. Also to understand wind patterns, one can hang a wind sock to see the patterns of flow. If you are doing consulting for even just one day, you can immediately hang a few pieces of light fabric designed to catch the wind so you can quickly see the pattern for that given day.

Temperature. Max/min temperature gauges can help when defining micro-climates. We used them in Nelson, New Zealand, to see exactly where we would have to plant to maintain a safer zone for frost sensitive plants such as Avocado, Macadamia, and Tamarillo. Thus we had three different gauges placed on the hillside that we checked daily to help guide use in our design work. After some weeks of observation of these instruments, patterns on the maps were determined and other design features were added to help define the micro-climate.

Written by Doug Crouch

Header Art by Anita Tirone